Molecular cytogenetics characterization of Rhinoclemmys punctularia (Testudines, Geoemydidae) and description of a Gypsy-H3 association in its genome

Cavalcante, Manoella Gemaque; Souza, Luciano Farias; Vicari, Marcelo Ricardo; Bastos, Carlos Eduardo Matos de; Sousa, Jaime Viana de; Nagamachi, Cleusa Yoshiko; Pieczarka, Júlio César; Martins, Cesar; Noronha, Renata Coelho Rodrigues

doi:10.1016/j.gene.2020.144477

Cited by 9 publications

(12 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The use of repetitive DNAs as chromosomal markers in reptiles has not yet been thoroughly explored. Usually, studies applying repetitive DNAs in turtles involve chromosomal localization of multigene families [Badenhorst et al, 2015;Cavalcante et al, 2018Cavalcante et al, , 2020aMatsubara et al, 2019] and in situ localization of satellite DNA sequences or transposable elements, restricted to a few groups [Badenhorst et al, 2015;Boissinot et al, 2019;Cavalcante et al, 2020b]. However, chromosomal painting and BAC-FISH for detecting single-copy genes has proven useful for identifying chromosomal rearrangements in reptiles in cytogenetic studies [Young et al, 2013;Badenhorst et al, 2015;Iannucci et al, 2019;Lee et al, 2019;Lisachov et al, 2019].…”

Section: Introductionmentioning

confidence: 99%

Comparative Cytogenetics of Four Sea Turtle Species (Cheloniidae): G-Banding Pattern and in situ Localization of Repetitive DNA Units

Machado

Glugoski

Domit

et al. 2020

Cytogenet Genome Res

View full text Add to dashboard Cite

Sea turtles are considered flagship species for marine biodiversity conservation and are considered to be at varying risk of extinction globally. Cases of hybridism have been reported in sea turtles, but chromosomal analyses are limited to classical karyotype descriptions and a few molecular cytogenetic studies. In order to compare karyotypes and understand evolutive mechanisms related to chromosome differentiation in this group, Chelonia mydas, Caretta caretta, Eretmochelys imbricata, and Lepidochelys olivacea were cytogenetically characterized in the present study. When the obtained cytogenetic data were compared with the putative ancestral Cryptodira karyotype, the studied species showed the same diploid number (2n) of 56 chromosomes, with some variations in chromosomal morphology (karyotypic formula) and minor changes in longitudinal band locations. In situ localization using a 18S ribosomal DNA probe indicated a homeologous microchromosome pair bearing a 45S ribosomal DNA locus and size heteromorphism in all 4 species. Interstitial telomeric sites were identified in a microchromosome pair in C. mydas and C. caretta. The data showed that interspecific variations occurred in chromosomal sets among the Cheloniidae species, in addition to other Cryptodira karyotypes. These variations generated lineage-specific karyotypic diversification in sea turtles, which will have considerable implications for hybrid recognition and for the study, the biology, ecology, and evolutionary history of regional and global populations. Furthermore, we demonstrated that some chromosome rearrangements occurred in sea turtle species, which is in conflict with the hypothesis of conserved karyotypes in this group.

show abstract

Section: Introductionmentioning

confidence: 99%

Comparative Cytogenetics of Four Sea Turtle Species (Cheloniidae): G-Banding Pattern and in situ Localization of Repetitive DNA Units

Machado

Glugoski

Domit

et al. 2020

Cytogenet Genome Res

View full text Add to dashboard Cite

show abstract

“…In turtles, three karyotypic groups were proposed according to the diploid number (2n): ( i ) high 2n (60 - 68 chromosomes) and high amount of mc; ( ii ) intermediate 2n (50 - 56 chromosomes) and relatively low amount of mc and; ( iii ) low 2n (26 - 28 chromosomes) and without mc ( Ayres et al ., 1969 ; Barros et al ., 1976 ; Sites et al ., 1979 ). However, genomic and cytogenetic studies using comparative analyses of chromosomal markers are scarce in Testudines species ( Iannucci et al ., 2019 ; Cavalcante et al ., 2018 , 2020a , b ).…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

“…The wide variation of 2n (26 - 68 chromosomes) observed in turtles implies that their genomes have been deeply reorganized ( Noleto et al ., 2006 ; Valenzuela and Adams, 2011 ; Montiel et al ., 2016 ; Noronha et al ., 2016 ; Cavalcante et al ., 2018 , 2020a , 2020b ; Clemente et al ., 2020 ). In this sense, the characterization of repetitive DNA sequences present in heterochromatin sites allow us to understand chromosomal rearrangements in some species of the group ( Cavalcante et al ., 2018 , 2020a , 2020b ). In turtles, as well as in sister groups, heterochromatin is located in the pericentromeric region of most macrochromosomes and some mc ( Nishida et al ., 2013 ; de Oliveira et al ., 2017 ; Cavalcante et al ., 2018 ; Barcellos et al ., 2019 ; Viana et al ., 2020 ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Heterochromatin and microsatellites detection in karyotypes of four sea turtle species: Interspecific chromosomal differences

et al. 2020

Self Cite

View full text Add to dashboard Cite

The wide variation in size and content of eukaryotic genomes is mainly attributed to the accumulation of repetitive DNA sequences, like microsatellites, which are tandemly repeated DNA sequences. Sea turtles share a diploid number (2n) of 56, however recent molecular cytogenetic data have shown that karyotype conservatism is not a rule in the group. In this study, the heterochromatin distribution and the chromosomal location of microsatellites (CA) n , (GA) n , (CAG) n , (GATA) n , (GAA) n , (CGC) n and (GACA) n in Chelonia mydas, Caretta caretta, Eretmochelys imbricata and Lepidochelys olivacea were comparatively investigated. The obtained data showed that just the (CA) n , (GA) n , (CAG) n and (GATA) n microsatellites were located on sea turtle chromosomes, preferentially in heterochromatic regions of the microchromosomes (mc). Variations in the location of heterochromatin and microsatellites sites, especially in some pericentromeric regions of macrochromosomes, corroborate to proposal of centromere repositioning occurrence in Cheloniidae species. Furthermore, the results obtained with the location of microsatellites corroborate with the temperature sex determination mechanism proposal and the absence of heteromorphic sex chromosomes in sea turtles. The findings are useful for understanding part of the karyotypic diversification observed in sea turtles, especially those that explain the diversification of Carettini from Chelonini species.

show abstract

“…Notably, in some cases, the telomeric motif TTAGGG is part of a larger satellite DNA sequence, and its presence and amplification in the genome is not directly connected to chromosomal rearrangements [ 68 , 69 ]. In turtles, the distribution of telomeric motifs have been studied up to our knowledge in 27 out of the 353 extant species [ 70 , 71 ], but ITRs have been previously reported in only six species [ 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ], reviewed further in this study, but more systematic survey is needed before drawing solid conclusions on the frequency of ITRs in turtles.…”

Section: Introductionmentioning

confidence: 99%

Interstitial Telomeric Repeats Are Rare in Turtles

Clemente

Mazzoleni

Pensabene

et al. 2020

Genes

View full text Add to dashboard Cite

Telomeres are nucleoprotein complexes protecting chromosome ends in most eukaryotic organisms. In addition to chromosome ends, telomeric-like motifs can be accumulated in centromeric, pericentromeric and intermediate (i.e., between centromeres and telomeres) positions as so-called interstitial telomeric repeats (ITRs). We mapped the distribution of (TTAGGG)n repeats in the karyotypes of 30 species from nine families of turtles using fluorescence in situ hybridization. All examined species showed the expected terminal topology of telomeric motifs at the edges of chromosomes. We detected ITRs in only five species from three families. Combining our and literature data, we inferred seven independent origins of ITRs among turtles. ITRs occurred in turtles in centromeric positions, often in several chromosomal pairs, in a given species. Their distribution does not correspond directly to interchromosomal rearrangements. Our findings support that centromeres and non-recombining parts of sex chromosomes are very dynamic genomic regions, even in turtles, a group generally thought to be slowly evolving. However, in contrast to squamate reptiles (lizards and snakes), where ITRs were found in more than half of the examined species, and birds, the presence of ITRs is generally rare in turtles, which agrees with the expected low rates of chromosomal rearrangements and rather slow karyotype evolution in this group.

show abstract

Molecular cytogenetics characterization of Rhinoclemmys punctularia (Testudines, Geoemydidae) and description of a Gypsy-H3 association in its genome

Cited by 9 publications

References 42 publications

Comparative Cytogenetics of Four Sea Turtle Species (Cheloniidae): G-Banding Pattern and in situ Localization of Repetitive DNA Units

Comparative Cytogenetics of Four Sea Turtle Species (Cheloniidae): G-Banding Pattern and in situ Localization of Repetitive DNA Units

Heterochromatin and microsatellites detection in karyotypes of four sea turtle species: Interspecific chromosomal differences

Interstitial Telomeric Repeats Are Rare in Turtles

Contact Info

Product

Resources

About